To provide an electromagnetic wave attenuator which is capable of attenuating electromagnetic waves from electronic equipment and preventing them from leaking out and generating negative ions around the electronic equipment so as to provide a comfortable environment for a human lightweight and small in size, and can be easily mounted on an equipment main body.

Mineral containing natural radioactive material is ground into powder, and the powdered mineral is mixed into ferrite material whose main component is iron oxide, a mixture of ferrite material mixed with the powered mineral is baked into a radioactive magnetic chip, a thin film of carbon steel is tensely disposed on the flat surface of the radioactive magnetic chip in one piece, an adhesive is provided to the radioactive magnetic chip, and a release paper is provided thereon so as to solve a problem.